If you look at the ingredients for Alka-Seltzer, you will find that it contains citric acid and sodium bicarbonate (baking soda). When you drop the tablet in water, the acid and the baking soda react -- this produces the fizz.
Shake and Bake A new and increasingly widespread technique also known as one pot, this condenses the anhydrous method's many steps and requires only a plastic soda bottle, the size of which depends on the quantity of meth the cook intends to make.
Bisquick Shake 'n Pour pancake mix comes in a plastic container that has the mix pre made and ready to go, all you have to do is add cold water to the fill-line, replace the lid and shake. The mix is then ready for use as pancake batter.